1. Field of the Invention
The present invention relates to an apparatus for exhausting gaseous fumes, and more particularly but not by limitation, to an improved adjustable exhauster arm assembly for capturing fumes at their source.
2. Brief Discussion of Prior Art
In the past, it was common to use large exhaust hoods or fans to remove industrial pollutants, such as welding smoke, grinding dust and other gaseous fumes. In recent years, however, it has become more common to remove these pollutants at their source with localized exhaust fans or blowers provided with maneuverable capture exhauster arms.
Several prior art exhauster arms have been proposed for capturing fumes at their source. One such arm is disclosed in U.S. Pat. No. 4,860,644, issued to Kohl et al. The Kohl et al. patent discloses an adjustable exhauster arm having internally disposed joint assemblies which are positioned adjacent the inside curvature of a flexible hose which surrounds the attaching assemblies. This internal structure makes adjusting the tension of the attaching assemblies inconvenient since the flexible hose must first be removed.
U.S. Pat. No. 4,158,462, issued to Coral, discloses an adjustable exhauster arm having externally disposed articulating structure. However, this structure is rather bulky and unsightly, and while the articulating structure of Coral is more accessible for making adjustments and repairs than the articulating structure disclosed in Kohl et al., it is inconvenient to do so. The Coral patent further discloses an elastic balancing assembly for supporting the exhauster arm. This balancing assembly does not provide solid support for the arm or allow for accurate and precise positioning of the arm.
U.S. Pat. No. 3,818,817, issued to Nederman, discloses an adjustable exhauster arm wherein an internal support structure extends the length of the arm and supports a flexible tubing extending between a fan and a suction hood.
While many of the prior art exhauster arms, including those taught by the above mentioned patents, have achieved varying degrees of success, such devices are relatively difficult to manipulate and inefficient to operate. The present invention provides for easy adjustment, less maintenance and precise positioning.